BeepStreet Impaktor, £2.99/$4.99

Impaktor is a new semi-modular drum synth from developer BeepStreet - the company behind iSequence, Sunrizer, GyroSynth and Pro Keys. The app is triggered via the device’s inbuilt mic, so can effectively be played using anything you can possibly make a percussive noise with.

Fluxama DR-OM, £1.49/$1.99

Fluxama’s DR-OM models the cult hacker-favourite sound generator of the same name. It replicates three different user-modified versions of the unit, each packing two LFOs and a voltage-controlled filter - perfect for creating psyc-ready drones.

Larson Associates John Cage Piano, 69p/$0.99

Compatibility: iPad (requires iOS 4.0 or later)

Launched to commemorate the legendary composer’s 100th birthday, John Cage Piano is a playable app sampling his iconic prepared piano - a piano percussively manipulated by placing objects, such as screws, nuts and bolts, around the strings.

Users can record and export their performances. A free iPhone version is also available, containing fewer sounds and lacking the ability to record.